core: Add allocated tag expiry, mctp_set_now_op()
Allocated tags expire after 6 seconds, requiring a time source.
The default will use clock_gettime(), though implementations can set
MCTP_DEFAULT_CLOCK_GETTIME=0 and use mctp_set_now_op() for custom
behavior.
Change-Id: Iaacf500bcd458c987f4b79c698bac9ae5ad5a73e
Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
diff --git a/core.c b/core.c
index 3a4ed89..e28f6bc 100644
--- a/core.c
+++ b/core.c
@@ -20,6 +20,10 @@
#include "compiler.h"
#include "core-internal.h"
+#if MCTP_DEFAULT_CLOCK_GETTIME
+#include <time.h>
+#endif
+
#ifndef ARRAY_SIZE
#define ARRAY_SIZE(a) (sizeof(a) / sizeof(a[0]))
#endif
@@ -238,6 +242,19 @@
return mctp;
}
+#if MCTP_DEFAULT_CLOCK_GETTIME
+static uint64_t mctp_default_now(void *ctx __attribute__((unused)))
+{
+ struct timespec tp;
+ int rc = clock_gettime(CLOCK_MONOTONIC, &tp);
+ if (rc) {
+ /* Should not be possible */
+ return 0;
+ }
+ return (uint64_t)tp.tv_sec * 1000 + tp.tv_nsec / 1000000;
+}
+#endif
+
int mctp_setup(struct mctp *mctp, size_t struct_mctp_size)
{
if (struct_mctp_size < sizeof(struct mctp)) {
@@ -246,6 +263,9 @@
}
memset(mctp, 0, sizeof(*mctp));
mctp->max_message_size = MCTP_MAX_MESSAGE_SIZE;
+#if MCTP_DEFAULT_CLOCK_GETTIME
+ mctp->platform_now = mctp_default_now;
+#endif
return 0;
}
@@ -893,11 +913,24 @@
msg_len);
}
+void mctp_set_now_op(struct mctp *mctp, uint64_t (*now)(void *), void *ctx)
+{
+ assert(now);
+ mctp->platform_now = now;
+ mctp->platform_now_ctx = ctx;
+}
+
+uint64_t mctp_now(struct mctp *mctp)
+{
+ assert(mctp->platform_now);
+ return mctp->platform_now(mctp->platform_now_ctx);
+}
+
static void mctp_dealloc_tag(struct mctp_bus *bus, mctp_eid_t local,
mctp_eid_t remote, uint8_t tag)
{
struct mctp *mctp = bus->binding->mctp;
- if (local == 0 || remote == 0) {
+ if (local == 0) {
return;
}
@@ -907,6 +940,7 @@
r->local = 0;
r->remote = 0;
r->tag = 0;
+ r->expiry = 0;
return;
}
}
@@ -916,17 +950,16 @@
mctp_eid_t remote, uint8_t *ret_tag)
{
assert(local != 0);
- assert(remote != 0);
+ uint64_t now = mctp_now(mctp);
uint8_t used = 0;
struct mctp_req_tag *spare = NULL;
/* Find which tags and slots are used/spare */
for (size_t i = 0; i < ARRAY_SIZE(mctp->req_tags); i++) {
struct mctp_req_tag *r = &mctp->req_tags[i];
- if (r->local == 0) {
+ if (r->local == 0 || r->expiry < now) {
spare = r;
} else {
- // TODO: check timeouts
if (r->local == local && r->remote == remote) {
used |= 1 << r->tag;
}
@@ -944,6 +977,7 @@
spare->local = local;
spare->remote = remote;
spare->tag = tag;
+ spare->expiry = now + MCTP_TAG_TIMEOUT;
*ret_tag = tag;
mctp->tag_round_robin = (tag + 1) % 8;
return 0;